remuneration based on productivity. help

hie guys may someone please help. shouldn’t basic pay be $360?
basic pay is $9/hour for a forty hour week.
normal production in that time =120 units.
bonus =50% of the time saved on production paid at time and third. what will be the total wage in a week in which 150 units are made in 40 hours?

answer
basic pay=45*$9 = 405
150 units should take 50 hours
150 units took 40 hours
hours saved 10 hours
bonus=50%*10*9*4/3 =60
total pay =465

shouldn’t basic pay be $360.